Modern inventory systems, such as those in mail order warehouses, supply chain distribution centers, airport luggage systems, and custom-order manufacturing facilities, can include a number of complex systems, including robots, automated shelving systems, radio frequency identification (RFID), and automated scheduling and routing equipment. Many systems, for example, include robots that travel to shelving systems to retrieve items, or the shelves themselves, and return them to a central location for additional processing.
Automated warehouses exist that use robots, for example, to move items or shelves from a storage location in the warehouse to a shipping location (e.g., for inventory items to be boxed and shipped) according to carefully planned and coordinated routes. However, the paths of a robot and one or more humans working in the warehouse may cross. Direct contact between the human workers and the robots can be problematic, and a maintenance and/or performance issue for the robots. For example, some robots may enter a stopped state if a human is detected nearby. This causes the robot to interrupt the task it is currently performing until the human leaves the nearby area or modify its route to avoid the human. The contact can also impact the rate at which the human worker can move through the workspace. For example, if many robots are traveling through a common area, the human worker may need to wait for the robot traffic in the common area to clear before proceeding.